This invention relates to surface treatment apparatuses and work carrying and handling systems thereof and more particularly to a handling system for conveying, lowering, and raising work articles being treated in metal surface treatment.
Metal surfaces of work articles are ordinarily subjected to a series of treatments in a batch type metal surface treatment apparatus which comprises a plurality of treatment liquid tanks arranged in a line for carrying out respectively different surface treatments and means for moving from one tank to the succeeding tank a conveying frame from which is suspended each work article to be treated and dipping the article in each tank in succession from the starting end to the terminal end of the line thereby to subject the article to each of the treatments.
In a handling system for accomplishing a carrying and handling operation of this character, conditions peculiar to surface treatment, in addition to the conditions to be met in a handling system for general industrial use, must be satisfied. Otherwise, there will arise not only problems in the handling of the work articles being treated but also problems due to adverse effect on the performance of the surface treatment.
More specifically, these conditions are related to the mutual relationship of the treatment tanks and the work articles to be treated (hereinafter referred to as articles), swinging of an article, prevention of deterioration of the electrical characteristics of a conveying frame and an article, prevention of an oblique entrance phenomenon when an article is plunged into a treatment liquor, shockless setting of a conveying frame on a conveying frame seat, reduction of the handling time, and reduction of driving power consumption.